Hand-carved arrowheads and jagged spears made of obsidian, a sharp rock formed by volcanic magma, are remnants of vast ...

Since it's born out of molten rock, obsidian is only found in volcanic regions of the world, including in parts of the United States, such as the Mountain West, Southwest, California, Oregon ...

For the ancestral peoples of the Pacific Coast, obsidian (volcanic glass) was a highly valued raw material because it could be used to make razor-sharp cutting tools. However, for many parts of the ...